Blasting cartridge charged with a compressed gas



Jan. 31, 1933. F, H, ARMSTRONG 1,895,553

BLASTING CARTRIDGE CHARGED WITH A COMPRESSED GAS Filed Sept. 16, 1932 Patented Jan. 31, 1933 FRANK H. ARMSTRONG, OF CHICAGO, ILLINOIS, ASSIGNOR T SAFETY MINING COM- ]?ANY, OF CHICAGO, ILLINOI3, A CORPORATION BLASTING CARTRIDGE CHARGED W'ITH A. COMPRESSED GAS Application flied September 16, 1932, Serial No. 633,406, and in France May 19, 1932.

This invention has for its object improvements in cartridges of the type in which a highly compressed gas is used as a blasting medium.

Cartridges of this type usually comprise a cylindrical steel case, adapted to receive a charge of liquefied or highly compressed gas,

and in which is arranged a device allowing to heat this fluid, by producing a chemical reaction, or by any other means, to vaporize it, increase the pressure of the gas charge, and thus cause the rupture of a suitable sealing device closing the case, and the escape of the gas into the material to be blasted in which the cartridge is placed.

The cartridge, according to the invention, is so devised that the explosion be provoked without the help of any heating means, the desired effect being simply obtained by releasing, by means ot a suitable de v1ce, acharge of highly compressed gas contained 1n the cartridge.

Two forms of construction of this cartridge will be hereinafter described by way of example only, with reference to the accompanying drawing, in which:

Fig. 1 is a partial vertical section of a first form of construction,

Fig. 2 is a similar view of a second form of construction,

Fig. 3 is a. perspective view of the supporting member for the sealin disc,

Fig. 4 is a plan view of the device for the remote control of the cartridge.

This cartridge comprises a case 1 having a chamber 2which contains a charge of gas compressed to a high pressure, for instance 5,000 to 10,000 pounds per square inch.

This chamber is hermetically sealed, in a known manner, by a steel disc 3, clamped against a shoulder 1a of the case 1 by a hollow cap 4 perforated with discharge holes 4a extending from its recess 46 to the exterior.

The disc 3 is so devised as to withstand only a pressure below that of the charge of gas in the case 1, for instance a pressure equal to one-half of that of this charge.

According to the form of construction illustrated in Fig. 1, the disc 3 isprevented from breaking until the cartridge is to be used by a toggle mechanism arranged in the recess 46 of cap 4.

This mechanism comprises two levers 5 and 6 pivotally connected together i at 7 and through the medium of which the center of the disc 3 bears upon an abutment-screw 8 screwed in the top of the cap.

The said levers are held in operative position by a finger 5a, formed for instance at the end of the lever 5 which carries the pivot 7, and abutting a ainst the wall of the recess 4?) (position indicated in full lines). For discharging the cartridge, the above mechanism is put out of action by breaking the rigid support it afl'ords to the disc 3, and, for that purpose, the levers 5 and 6 are caused to pivot to the position indicated in dot and dash lines, in which the lever 5 is moved away from the disc.

This operation can be efi'ected from a distance,-for instance by means of a cable 9.

In these conditions, the cartridge can be charged with a gas having the necessary pressure for producing the desired eflect; the said cartridge can be transported to the place of utilization where it is suitably inserted in position, whereupon, by means of the cable 9, the levers 5 and 6 are moved to inoperative position. The disc 3, being no longer supported, is ruptured and the gas escapes into the material to be blasted through the holes of the cap 4.

The form of construction illustrated in Figs. 2 to 4 also comprises a sealing disc 3 so devised as to withstand only a pressure below that of the charge of gas contained in the chamber 2. As in the preceding case, its resistance corresponds for instance to a pressure equal to one-half of that of this charge.

The necessary reinforcement of this disc for allowing it to support such a pressure is afforded by a second disc 10 interposed between the disc 3 and the discharge cap 4.

This disc 10 is embossed, so as to form, at its periphery, bent flanges 10a through the presses upon the disc 3, a hollow 10?) also pressing clamped on the disc 3 by the cap 4, an empty space 11 exists between both discs.

This space 11 is connected to the chamber 2 by a passage 12, provided in the wall of the case 1, and normally sealed by a valve 13.

The valve 13 is provided, outside the cartridge, with a circular head 14 in the shape of a pulley, in the groove of which is secured an operating cable "15 so arranged that by pulling this cable the needle valve 18 opened.

The disc 10 too is so devised as to have a resistance below that necessary for withstanding by itself the pressure existing in the chamber 2, but the combination of both discs 10 and 3 allows them to withstand this pressure and to insure the sealing of the said chamber.

The operation is as follows:

When the cartridge is in position, the operation of the cable 15 causes the opening of the valve 13 and the admission of the compressed gas into the space 11.

The disc 10, directly subjected to this pressure, is ruptured, and the disc 3, deprived of its support, is ruptured immediately after.

The device according to the invention allows to transport a charge of a highly compressed gas from the charging station to the point of use and to operate it with the greatest case, without the help of electric or thermal means of any kind whatever. This latter advantage is particularly important concerning safety.

Although a gas of any nature may be used as a blasting medium, the use of liquefied carbonic dioxide is preferred, owing to its high density.

The invention is not of course limited to the forms of construction herein above described by way of example only, and, without departing from the scope of said invention, use can be made of any suitable sealing devices cooperating with supporting elements so devised as to be put out of action at the required moment, either by purely mechanical means, or by the very pressure of the charge of the cartridge, etc.

What 1 claim is:

1. A material blasting device comprising a container constructed to withstand any pressures to which it might be subjected while performing the work for which it is designed, a charge of gas within said container at a pressure sufficient to perform said work, and means for liberating said charge when desired.

2. A material blasting device comprising a container having therein a charge of gas of sufiicient volume and pressure to perform the desired work in relation to a particular material, and means for liberating said charge when desired, said container being reusable.

3. A material blasting device comprising a reusable container having therein a charge of gas of suflicient volume and pressure to perform the desired work in relation to the particular material to be treated, and means operable from a remote point for instantaneously liberating said charge.

4. A material blasting device comprising a reusable container having therein a charge of compressed gas at work performing pressure, and controllable means for liberating the charge at such pressure.

5. A material blasting device comprising a container for confining a charge of compressed gas at work performing pressure and means operable from a remote point for suddenly liberating the charge without prior change of condition of the charge.

6. A material blasting device comprising means capable of confining a charge of compressed gas at Work performing pressure, and mechanical means associated with the device for liberating said charge.

7. A material blasting device comprising means capable of confining a charge of compressed gas at work performing pressure, and mechanical means associated with said device and subject to actuation from a remote point for liberating said charge.

8. A material blasting device comprising a container having av discharge opening therein, a rupturable closure for said opening, a

charge of gas at work performing pressure within said container, said closure being of insufficient strength to alone withstand the pressure of said charge, and means for preventing failure of said closure until release of said charge is desired.

9. A material blasting device comprising a container having a discharge opening therein, a rupturable closure for said opening, a charge of gas at work performing pressure within said container, said closure being of insufficient strength to alone withstand the pressure of said charge, and means for supporting said closure against said pressure, said support being subject to withdrawal at will, thus, resulting in instantaneous failure of said closure and liberation of said charge.

10. A material blasting device comprising a charge of energy in work performing condition confined within a substantially indestructible container, and means associated with said container for effecting release of said charge when desired without altering the condition thereof.

11. A device for blasting coal comprising a container having therein a charge of gas of suflicient volume and pressure to produce the desired results, said container adapted to be placed in a drill hole in the coal to be broken and means associated with said container so positioned in the drill hole for remeans associated with the device for ing said charge at said pressure. I

13. A material blasting device comprising means capable of holding a charge of compressed gas at work performing pressure, and means associated with the device and sub ect to controlled actuation from a remote point for liberating said charge at said pressure.

14. A material blasting device comprising a container having a discharge opening therein, a closure for said opening, a charge of gas at work performing pressure within said container, said closure being incapable alone to prevent the release of said charge through said opening, and means for assisting the closure to hold the charge, said means being operable at will to withdraw its assistance to cause the charge to be released.

15. A material blasting devicecomprising a container having a discharge opening therein, a closure for said opening, a charge of gas at work performing pressure within said container, said closure being incapable alone to prevent the release of said charge through said opening, means for assisting the closure to hold the charge, and means controllable liberat from a remote point for causing the last mentioned means to be withdrawn at will from assisting the closure, thus, resulting in instantaneous liberation of said charge.

16. A material blasting device comprising a container having a discharge opening therein, closure means for said opening, a charge of gas within said container of suflicient volume and pressure .to produce the desired results, said closure means being of suflicient strength to hold the charge against liberation through said opening, and means operable at will to cause failure of said closure means to bring about liberation of the charge.

17 A method of blasting material which comprises confining a charge of gas compressed to a pressure capable of performing the intended work within a depression in said material, and liberating said charge from its confinement, without substantial change in pressure when desired to permit the gas to expand to perform its intended work.

18. A method of blasting material which comprises confining in a suitable container a charge of gas compressed to a pressure capable of performing the intended work, placing the charged container in work performing relation with respect to the material to be broken, discharging the charge of gas from the container without substantial change in pressure to permit the gas to expand to perform its intended work, and controlling the direction of discharge of the gas with respect to the said material.

Signed at Chicago, Illinois, this 14th day of September, 1932.

FRANK H. ARMSTRONG. 

